The Pd-catalyzed copper-free carbonylative Sonogashira coupling reaction to synthesize alkynyl ketones from terminal alkynes and aryl iodides was achieved by using water as a solvent. The reaction was carried out at room temperature under balloon pressure of CO with Et(3)N as a base. The developed method was successfully applied to the synthesis of flavones.

[reaction: see text] A concise synthesis of the core structures of plecomacrolide with ring sizes varying from 16 to 19 atoms was achieved for the first time by the diene-ene ring-closing olefin metathesis reaction. This approach should allow access to the structurally diverse analogues of plecomacrolide.

Ketones Q 0350Pd-Catalyzed Copper-Free Carbonylative Sonogashira Reaction of Aryl Iodides with Alkynes for the Synthesis of Alkynyl Ketones and Flavones by Using Water as a Solvent. -(LIANG, B.; HUANG, M.; YOU, Z.; XIONG, Z.; LU, K.; FATHI, R.; CHEN*, J.; YANG, Z.; J. Org. Chem. 70 (2005) 15, 6097-6100; Key Lab. Bioorg.